Vacuum-tube device



April 1929- l, E. MOUROMTSEFF VACUUM TUBE DEVICE Filed April 28. 1925INVENTOR [/[0 E. Mawvmfse/f WITNESSES:

ATTORN EY Patented Apr. 2, 1929.

UNITED STATES PATENT OFFICE.

ILIA EMMANUEIi MOUROMTSiEFF, OF WILKlINSBURG, PENNSYLVANIA, ASSIGNOR TWESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, .A CORPORATION OFPENNSYLVANIA.

VACUUM-'1 Application filed April 2 My invention relates to vacuum-tubedevices and particularly to structural details of such devices which areadapted for the translation of relatively high electrical energy values.

An object of'my lnvent on is to provlde a high-power oscillator trlodewith a. grid lead whlch is capable of carrying a substantial ambunt ofcurrent.

Another object of my invention is to provide a grid lead constructionadapted for convenient insertion through a seal.

Another object of my invention 1s to simplify the structural details ofvacuumtube devices.

In the prior art, triode tubes have been constructed which are adaptedto the translation of power as great as 10 kw. of electrical energy.These triode devices are adapted to the generation of radio-frequencyoscillations. Such devices function adequately at frequencies of theorder of about 1500 kilo-cycles per second without particulardifficulty, but at higher frequencies of generation difficulty has beenexperienced in leading to the grid, or control electrode, the necessarycharging, current to cause the operation of generation to take place.=The tubes as previously constructed, were builtwith a wire conductorsealed through a portion of the glass container. Within the container, acoiled flexible wire of smaller diameter was attached -'to the seal Wireand was also attached to a wire leading to the grid structure. Theoperation of sealing the conductor through the glass required that aportion'of the lead within the container be flexible. This wasconveniently attained by the coiled wire mentioned.

However, when the triode was used for the generation of frequenciesabove the order of about 1500 kilo-cycles, the small size and coiledcharacter of this wire resulted in the generation of an undesirableamount 7 of heat therein by reason of ohmic losses, eddy currents, andthe skin efiect in the coiled .conductor. -Myinvention provides asimplified, flexible grid lead which is adapted to be convenientlysealed through the glass of the container, and which has a suflicientlyhigh conductivity to reduce losses to such value that difliculty enced.

Other objects and structural details of my invention will be apparentfrom the following description when read in connection with theaccompanying drawing wherein,

Figure 1 is a view in vertical sectional elevation of a triodecontaining an embodiment of my invention; and

Fig. 2 is a detail View ofth tion of a grid lead therein.

Referring to the figures, a metal shell electrode 1 is attached to aglass closure 2 by a seal 3. Within the metal shell 1 is positioned afilamentary cathode 4 and a control electrode 5 having a supportingmember 6 clamped to a re-cntrant portion 7 oi the closure 2. To thecontrol electrode support 6 is attached a conductor 8., A conductor 9 issuitably sealed through the wall of the glass closure 2. Connection ismade between the conductors 8 and 9 by a number of strips 11 preferablyflattened and of conducting material which may be connected, as by spotwelding, at their respective ends to the conductors 8 and 9 and may befur ther held in position by wire wrappings 12 and 13.

The conductors 8 and 9 are preferably of tungsten or molybdenum and theconnector portions 11 areprefe'rably strips of molyb- L denum. Thebinding wires 12 and 13 are also preferably of molybdenum.

The strips of molybdenum ofler sufficient conductivity to the current topermit conduction therethrough without excessive resistivelosses.Likewise, the fact that the conductive pieces are bent through only aportion of a turn instead of being coiled as was previously done removesthe inductive action which produced the skin cited. in priorconstructions, resulting in increased losses. My construction alsoreduces the eddy currents and thus removes a large part of such losses.Thus, the conductive lead ismaintained at a satisfactory temperatureduring operation of the tube.

In the'assembly of .the' device, the flexibility of the'strips ofmaterial 11 is sufiicient to permit the construction of a satisfactory.seal for the conductor 9 through the glass 2.

By means of this construction, I am enwith heating is notexperiefiexible perabled to simplify the manufacture of a vacuum-tubedevice and to improve its operating characteristics.

While I have shown but a single emhodiment of my invention, it iscapable of various modifications thereof and it is desired, therefore,that only such limitations shall be. imposed thereon as are required bythe prior are or indicated in the appeni led claims.

I claim as my invention:

1. In a space current device, the combination of a container comprisinga metallic portion and a vitreous portion, said metallic portioncomprising an anode,a control electrode and a filamentary cathode Withinsaid container, a lead sealed in a side Wall of said vitreous portion,and a lamellar connection between the inner end of said lead and saidcontrol electrode.

2. In a space current device, the coml ination of a container comprisinga metallic portion and a vitreous portion, said metallic portioncomprising an anode, a control electrode and a filamentary cathodewithin said container, a lead sealed in a side wall of said vitreousportion, and a connection between the inner end of said lead and saidcontrol electrode, comprising superposed laminations; of molybdenum.

In testimony whereof, I have hereunto subscribed my name this 22nd dayof April, 1925.

ILIA E. MOUROHTSEFF.

